Drivers and impacts of insect biodiversity changes across pantropical forests

Safeguarding insect biodiversity has a global impact. Insects increase crop yields, help food production and economies, and are essential for ecosystem functioning. Scientific research and expertise must, therefore, ensure we not only understand what is causing global insect biodiversity changes but also enable us to mitigate the further consequences for nature and people. Tropical forests are an ideal setting to investigate the occurrence, drivers and consequences of insect biodiversity loss because they are home to much of Earth's terrestrial biodiversity - including the majority of all known species, and provide many ecosystem services upon which humanity relies.

Despite the growing number of academic studies and media headlines drawing attention to 'collapses in insect biodiversity', the status of insect populations continues to attract insufficient research attention. This bias is evidenced by the fact that only c. 1% of all described insects have had their conservation status assessed by the IUCN compared with 72% of vertebrates. Our ability to inform better environmental decision-making and conservation policy-making is further limited by other three factors. First, the tropics have been mostly overlooked in previous large-scale and long-term assessments of insect biodiversity trends. Second, little is known about how the use of agricultural pesticides affects tropical insect populations in nearby forests. Finally, our knowledge of insect interaction networks within tropical forests is limited to a few assessments based on single locations or model taxa. As a result, we continue to miss a broader picture of the nature and scale of changes in tropical insects' diversity and populations, the factors driving these changes, and the further consequences for forest function and stability.

To redress these gaps in our understanding, my research aims to: 1) investigate the occurrence, scale and causes of changes in tropical insect biodiversity; 2) quantify the impacts of agricultural pesticides and heavy metals on insect populations; 3) determine the cascade effects of insect loss for their interactions with other biological groups; and 4) promote biodiversity conservation through forecasting how distinct scenarios of climate change and land-use intensification will affect tropical insects to inform the decision-making. To achieve this, I will establish the first pantropical insect monitoring programme with standardized methods in Amazonian, African and Asian forests. This information will be combined with state-of-the-art ecotoxicology, metabarcoding, remote sensing and ecological modelling techniques to assess disturbance-driven impacts on insect communities and populations, changes in interaction networks with other taxonomic groups, and the contamination by distinct pollutants. Moreover, I will integrate information generated through the fellowship with large-scale spatialized insect abundance data from the study regions to forecast the impacts of further climate and land-use changes on insect biodiversity. To achieve impact and inform practices and policies, I will engage with distinct stakeholders in the study regions.

To the best of my knowledge, this will be the first pantropical study aiming to investigate spatiotemporal changes in multiple insect groups surveyed with standardized methods in tropical forests. In doing so, my research will help us to understand the causes and mitigate the consequences of changes in tropical insect biodiversity; and generate data that will inform policy-making and biodiversity conservation strategies in the hyperdiverse tropics.